Gravitational Waves from Cosmic Strings

Orador/Speaker: José Juan Blanco-Pillado (UPV-Ikerbasque, Bilbao, Spain) Data, hora e local: 8 de março de 2016, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo/Abstract: In this talk I will describe the formation and evolution of a network of cosmic strings focusing in particular on the latest results from the largest numerical simulations…

Naked Firewalls

Orador: Yen Chin Ong (Nordita, Sweden) Data, hora e local: 24 de fevereiro de 2016, às 11h30m na sala de reuniões do Departamento de Matemática. Abstract: In the firewall proposal, it is assumed that the firewall lies near the event horizon and should not be observable except by infalling observers, who are presumably terminated at…

The Palatini approach in gravitation

Orador: Diego Rubiera-Garcia (Universidade de Lisboa) Data, hora e local: 16 de fevereiro de 2016, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: We propose a formulation to modified theories of gravity where metric and affine connections are independent. Besides some interesting mathematical properties (like second-order field equations and absence of ghosts)…

Optimal Estimators for Normal Orthogonal Block Structures

Orador: Prof. Doutor João Tiago Mexia (Professor Catedrático Jubilado, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa). Data, hora e local: 15 de fevereiro de 2016, às 16h na sala de reuniões do Departamento de Matemática. Resumo: Mixed models whose variance-covariance matrices are the positive definite linear combinations of pairwise orthogonal orthogonal projection matrices…

Superradiant scattering in astrophysical binary systems

Orador: João Rosa (Universidade de Aveiro). Data, hora e local: 11 de fevereiro de 2016, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: I will discuss the generic properties of gravitational plane wave scattering in the Kerr spacetime. I will then show how these results can be applied to realistic astrophysical systems…

Cosmological singularities in Eddington-inspired-Born-Infeld theory and its possible extension

Orador: Che-Yu Chen (National Taiwan University). Data, hora e local: 3 de fevereiro de 2016, às 11h30m na sala de reuniões do Departamento de Matemática. Resumo: The Eddington-inspired-Born-Infeld (EiBI) gravity, which is formulated within the Palatini formalism, is characterized by its ability to cure the Big Bang singularity in the very beginning of the Universe.…